Stanisław II August II (1732-1798), also known as Stanisław Augustus Poniatowski, was the last king of Poland and Grand Duke of Lithuania (1764-1795). He belonged to an aristocratic family in Poland-Lithuania and was elected king with the support of the Russian Empress Catherine II, with whom he had a close personal relationship.

As king, he tried to modernise the state, promoting educational and administrative reforms. He was the initiator of the Constitution of 3 May 1791, the first written constitution in Europe, which aimed to strengthen central power and reorganise the Polish Commonwealth. However, his reign was marked by political instability and interventions by foreign powers. The state was eventually subjected to three successive divisions (1772, 1793, 1795), which led to the dissolution of Poland.

Augustus Stanislaus II was an active member of Freemasonry and participated in many Masonic lodges, promoting the ideas of the Enlightenment. After his resignation in 1795, he spent the last years of his life in St. Petersburg, where he died in 1798.

He was an important figure of the Enlightenment, despite his inability to preserve Poland’s independence.